Offset tool generating high number of points

I’ve noticed that the offset tool creates a lot of node points.

The outside object is still an ellipse primitive, the nodes are numerous.

This outside object had been converted to a path, again with significant numbers of nodes.

If I cut and paste and manually scale (90% in this case per iteration), the number of nodes doesn’t change, although the shape doesn’t stay the same, due to the nodes moving relative to each other.

These offsets were performed with ‘optimise’ switched on. Is it possible to affect how much optimisation is performed?

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Less interested in assumptions than the developer’s take on it, thanks all the same.

The offset system only works with line segments, so everything is converted to them, then back again by refitting to arcs and linear segments. If you have something that doesn’t actually fit as an arc, it can create a lot of smaller segments. It can also be affected by your output tolerance (set at the bottom right of the settings) if the value is very small.

One of the devs is working on integrating better curve re-fit tool, which we hope to use for more things like this. Instead of just doing simple arcs it will recover proper splines within some distance tolerance, and that will result in far fewer segments for cases like this.

The node count isn’t as bad as you might think - the semi-transparent blue ones are the tangent handles, and while it looks messy, the real nodes aren’t as dense:

Nodes with spline tangent handles:
Snag_5184f57d

Just nodes:
Snag_51851b64

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I appreciate both the question (as I have observed the same and was curious as well) and the answer.

Thanks for that.

I looked for a tuning option - I must be blind, I’ll go back and look at the output tolerance setting.

I’m not even 100% positive that it’s used (I think it is, as it’s used for a number of internal things like this), but would be the only thing that controls it for the moment.

Oh, I misunderstood - so not on the offset tool itself?

Correct - it’s a global setting that is used for all kinds of things, including converting splines to segments when generating the output to the machine itself. The default is 0.05mm. Going too large with it can produce jerkier motion, so be careful if changing it.

As I said, we’re working on a better spline re-fit tool that will be used instead of just arc fitting, and that will help in cases exactly like yours where the offset result isn’t just arcs.

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